A reflector and a light source can form, for example, basic components of a module for providing a low-beam light or a high-beam light in a vehicle headlamp. The vehicle headlamp could also be understood as a general lighting device for a vehicle, for example, as a rear tail lamp. Here it is known to insert the light source in a back-side opening of the reflector, in order to then rotate this light source in the opening over a certain angle range. Here, retaining arms arranged on the light source grip under defined areas of the retaining ring, so that the light source is arranged on the reflector on the back side by the retaining ring like a kind of bayonet coupling. For this, the retaining ring must be arranged on the reflector, for which regular threaded connections are provided. The reflector can be formed in one piece and can have a mounting neck in which the opening for holding the light source is formed. The mounting neck can also be formed as an individual component and connected to the reflector body. For the assembly of the retaining ring on the reflector, the reflector is usually supplied with the opening facing upward on a means of transport, wherein the retaining ring must be placed on the opening for the later fastening to threaded elements.
For the transport of the reflector with the means of transport, for example, with a conveyor belt, vibrations can be introduced into the reflector, wherein these vibrations lead to the placed retaining ring falling onto the top-side opening of the reflector. Here it must be ensured that the retaining ring is precisely positioned on the opening of the reflector for the subsequent, often automatic fastening by the threaded elements. Therefore, if the retaining rings slip or fall down, manual help is needed to place the retaining ring back to its precise position on the opening of the reflector. Here it is disadvantageous to use bonding agents because these require a drying time and it is desirable to secure the retaining ring in position directly after placement on the opening of the reflector, in order to feed the reflector with the placed retaining ring for the subsequent automated fastening process.
As an alternative to the fastening of the retaining ring, there are solutions that involve, for example, a clipping of the retaining ring on the reflector. For example, U.S. Pat. No. 5,938,323 A1 shows a mount for a light source in the opening of a reflector for a vehicle headlamp and a retaining ring for placement on the reflector is provided that has a base body and extends in the plane of a ring. For fastening the retaining ring to the opening of the reflector, the retaining ring has locking clips by means of which the retaining ring can be clipped to the opening of the reflector. The locking clips project perpendicular from the plane of the retaining ring and form barbed hooks so that the locking clips can be clipped into openings formed on the reflector. Retaining rings with barbed hooks are disadvantageous in automated assembly, for example, when the retaining ring is to be automatically gripped by an assembly machine and placed on the opening of the reflector, because when the retaining ring is gripped by the barbed hook, several retaining rings can become hooked together, which would impair an automatic operation.
EP 0 900 974 A2 shows another mount for a light source in the opening of a reflector for a vehicle headlamp and a retaining ring is shown with which the light source is held in the opening of the reflector. The retaining ring has a plurality of expansion elements, holding elements, and fixing tabs that each form undercuts. This likewise prevents or makes automated handling of the retaining rings more difficult.
The mounting neck arranged on the reflector is often formed as a plastic component and is produced using an injection molding method. Here it is desirable to form the mounting neck without undercuts, in order for the injection molding tool to have the simplest possible shape. If the retaining rings have barbed hooks, these must lock into undercuts so that the advantage of a simple injection molding tool cannot be achieved. If the retaining ring is clipped on the mounting neck, with the mounting neck having corresponding geometries, these must usually also be provided with undercuts, so that a clipping of the retaining ring on the reflector also does not form a satisfactory solution.